The right front brake seems to be locking up on my wife's 97 F 150 4.6L. Needless to say that she has a hot rim. ... On the truck that is. Annnnyway..... I noticed that the brake fluid is circulating in the reservoir when the engine is on. It reminds me of water circulating in a radiator when the thermostat opens. Does this sound like it's time replace the master cylinder?
Thanks ahead of time for helping.
Jay

 

Sounds like you need to replace the right front brake caliper first.